It is B because I had to do this question to
Through isotopic analysis, forensic scientists can identify mutilated or deteriorated body, they can also identify his geographic location and life history. <span />
Carbohydrate is the answer
I think it's the nucleus. Isn't the nucleus the brain of the cell?
The variations might help the organism to survive if there is a change in its environment
Eg heat resistant bacteria
The variation might help the organism survive predators
Eg. Green beetles blend with green leaves thus disabling crows to spot them
:)